Means for attaching blade-shaped guides or supporting members in grinding machines, especially centerless grinders



3,040,48 7 RTING June 1962 A. o. KAMPE MEANS FOR ATTACHING BLADE-SHAPEDGUIDES OR SUPPO MEMBERS IN GRINDING MACHINES, ESPECIALLY CENTERLESSGRINDERS Filed Feb. 25, 1960 mvgmrom ANDERS OLOF' KAM PE AT TYS.

United States Patent MEANS FOR ATTACHZNG BLADE-SHAPED GUIDES RSUPPORTING MEMBERS IN GRIND- ING MACHENES, ESEECIALLY CENTERLESSGRIPEERS Anders Olaf Kiirnpe, Liclkoping, Sweden, assignor toLidkiipings Mekaniska Verkstads Aktiebolag, Lidkoping, Sweden, acorporation of Sweden Filed Feb. 25, 1960, Ser. No. 10,922 1 Claimspriorit application Sweden Mar. 2, 1959 4 Claims. (Cl. 51238) Thepresent invention relates to means for attaching blade-shaped guides orsupporting members in grinding machines, especially centerless grindingmachines, and has for its purpose to improve the accuracy of certainparts which determine the accuracy of the grinding operation, forinstance templets and supporting blades. Cylindrical or otherwise shapedwork pieces are often ground by the method known as plunge grinding, inwhich the grinding wheel is shaped to suit the work pieces being groundby means of a dressing tool, such as a diamond, or by means of any othersuitable tool, after which the grinding operation is carried out byfeeding the grinding wheel radially towards the work piece. Very greataccuracy is often required when grinding by this method, in many casesbeing of the order of one-thousandth of a mm.

When dressing the grinding wheel the tool is usually guided by a templetof such shape that as the dressing tool passes to and fro across thegrinding wheel, it generates the proper shape required for the grindingof the work piece. The templet is dernountable and exchangeable andpreferably fixed to a support by screws which pierce the templet atcertain distances from each other. The templet is engaged by a contactfinger which is pressed against the templet by means of a helical springor the like. The pressure of the contact finger against the templet mustbe great enough to counteract the pressure between the tool and thegrinding wheel to make sure that the tool follows the contour of thetemplet.

Because of the great accuracy which is often required when grinding inthis manner, the templet which determines the shape of the grindingwheel must be accurately fixed to its support so that it will not bedeformed either by the fixing means or when the contact finger passesalong the templet. It has been found that the usual manner of fixing thetemplet by merely screwing it to its support is not always satisfactory.A certain amount of yielding takes place in the portions of the templetbetween the screws with the result that the contour of the templet isdistorted and the desired form cannot be accurately transferred to thegrinding wheel. The present invention has for its purpose to avoid thesedisadvantages in a simple and practical manner.

The invention may be applied to grinding machines by means of screws orthe like between a support and p a pressure plate and is characterizedmainly thereby that a pressure distributing member is applied betweenthe blade-shaped member and the pressure plate, said pressuredistributing member comprising one or more elastic inserts of rubber orthe like and having substantially the same size and shape as thepressure plate.

By suitably choosing the dimensions of the pressure plate, the thicknessand elasticity of the insert and the distance between the screws, thepressure to which the blade is subjected will be distributed so thatvariations in pressure and thereby changes in shape along the length ofthe blade will be kept within a predetermined permissible value.

Although the invention is intended mainly for use in 3,940,487 PatentedJune 26, 1962 attaching templets for the dressing of grinding wheels, itmay also be used for fixing the supporting blade in centerless grindingmachines, where it has been found that it will in many cases be of greatadvantage.

In machines of this kind it is necessary when grinding Work piecesaccording to the method mentionedabove, that the work pieces rest on anaccurately fifxed unyielding support if the necessary accuracy is to beobtained. It has been found that it is difiicult to keep the contactingsurfaces between the blade and the pressure plate entirely free fromforeign substances, which cause deformation of the blade either when itis being fi xed in place or due to the load to which it is subjectedduring the grinding operation.

The invention is illustrated in the accompanying drawings, in whichFIGS. 1 and 2 show a form of the invention as used for fixing a templetfor dressing grinding wheels, wherein FIG. 1 shows the device partly insection as seen in the direction of the axis of the grinding wheel andFIG. 2 is a view from above of the same device on a somewhat smallerscale. FIG. 3 shows another form of the invention as used for fixing awork rest blade member in a centerless grinder.

In FIGS. 1 and 2 the numeral 1 indicates a grinding Wheel and 2 is atool for dressing the wheel, for instance a diamond. The diamond 2 isfixed to a holder 3 which in its turn is mounted on a cross slide 4movable in a direction perpendicular to the axis of the grinding wheel.The cross slide 4- is in its turn mounted on aslide 5 which is movableparallel to the axis of the grinding wheel by means of a screw 21. Theholder 3 is adjustable in its axial direction relative to the crossslide 4 by means of a screw 17, whereby the diamond can be moved in adirection towards the grinding wheel. The diamond is thus movable in twodirections perpendicular to each other in the same plane. A helicalspring 8 which at one end thereof engages with a shoulder 19 on thecross slide 4 and at its other end engages a shoulder 20 on the slide 5presses the cross slide 4 towards the left in the figure, until the edge18 of the contact finger 7 on the cross slide 4 engages with thecontoured edge of the templet 6 which determines the shape of thegrinding wheel 1. The templet is connected to a fixed base 22 of theframe of the machine by means of screws 11 through which it is fixedbetween a pressure plate 9 and the base. A resilientpressure-distributing member in the form of an elastic insert 10 ofsubstantially the same size and shape as the pressure plate is appliedbetween the templet and the pressure plate. In the present instance thepressure plate 9 is of generally rectangular shape and the elasticinsert 10 is coextensive with the pressure plate 9'.

In FIG. 3 which shows the invention applied to a centerless grindingmachine, the numeral 1 designates a grinding wheel, 16 is a regulatingwheel, and 13 a work rest blade member having oppositely disposed facesand an elongated supporting edge for supporting a round 7 workpiece 14.The work rest blade 13 is fixed to a fixed machine part 15 in a mannersimilar to that shown in FIGS. 1 and 2, i.e. by means of a pressureplate 9 and screws 11. The pressure plate 9 presses the supporting blade13 against its support 15 via an insert 10 of rubber or the like.

I claim:

1. Ina grinding machine having a support and a blade member havingoppositely disposed faces and an elongated supporting edge, means forsecuring said blade member to said support with one of said facesengaging said support, comprising a pressure plate disposed adjacent theother face of said blade member, a resilient pressure-distributingmember interposed between said pressure plate and said blade member, andfastening means securing said pressure plate, resilientmember and blademember together and to said support, said pressure-distributing memberoperable to prevent local elastic distortion of the supporting edge ofsaid blade member.

2. In a grinding machine having a fixed support and a generallyrectangular blade member having oppositely disposed faces and anelongated supporting edge, means securing said blade member to saidsupport with one of said [faces engaging said support, comprising agenerally rectangular pressure plate disposed adjacent the other face ofsaid blade member and coextensive in length therewith, at least oneresilient pressure-distributing member interposed between said pressureplate and blade member, and co-extensive in length with said pressureplate and blade member, and a plurality of fastening elements securingsaid pressure plate, resilient member and blade member together and tosaid support member, said pressure-distributing member operable toprevent local elastic distortion of the supporting edge of said blademember.

3. In a grinding machine having a support, a dressing tool movablymounted on said support and a template having oppositely disposed facesand a contoured edge for guiding movement of said dressing tool, meansfor securing said template to said support with one of said facesengaging said support, comprising a pressure plate disposed adjacent theother face of said template, a

resilient pressure-distributing member interposed between said pressureplate and template, and fastening means securing said pressure plate,resilient member and ternplate together and to said support, saidpressure-distributing member operable to prevent local elasticdistortion of the contoured edge of said template.

4. In a centerless grinding machine having a support and a work restblade member having oppositely disposed faces and an elongated worksupporting edge, means for securing said blade to said support with oneof said faces engaging said support, comprising a pressure platedisposed adjacent the other face of said blade, an elongated resilientpressure-distributing member interposed between said pressure plate andblade member, said pressure plate and distributing member being spacedfrom the elongated work supporting edge of said blade, and fasteningmeans securing said pressure plate, resilient member and blade membertogether and to said support, said pressure-distributing member beingoperable to prevent local elastic distortion of the work supporting edgeof said blade.

References Cited in the file of this patent UNITED STATES PATENTS1,585,984 Heim, May 25, 1926 2,751,109 Moore June 19, 1956 2,761,347McKee Sept. 4, 1956

